Sickle Cell Disease Flashcards
What is the Malarial Parasite?
Plasmodium falciparum
Diagnostic screening for newborns, what test?
hemoglobin electrophoresis
What two tests are used to confirm results?
DNA sequencing or Restriction Fragment Length Polymorphism analysis
What are prenatal tests?
chorionic villous sampling or amniocentesis or screening of newborn blood.
Codon 6 to lysine leads to the generation of what sickle disease?
HbC
disorder of hemoglobin synthesis
Thalassaemia
Hereditary persistence of fetal hemoglobin
HPFH
Treatment used to screen for stroke potential?
Transcranial Doppler
high blood flow velocity and lower hemoglobin levels can be related to ….? How do you Treat?
Children with SCA, Treatment includes red blood cell transfusion
When skeletal muscle or cardiac tissue is damaged, what happens?
myoglobin is released from cells and can turn urine red (myoglobinuria).
Accumulation of the heme degradation produces what?
bilirubin is associated with scleral icterus.
What are the results of increased bilirubin stored in the gallbladder?
it can precipitate to form stones (upper quadrant ultrasound)
what happens when RBC membrane proteins aggregate?
Create negative charge, leading to adherence to vessel walls and altering permeability of the cell resulting in dehydration
What are the results of vascular occlusions?
low blood flow or hypoxia
which leads to necrosis and pain
what is the benefit of low iron?
results in decreased hemoglobin S concentrations and decreased sickling
What genetic inheritance is considered with sickle cell disease?
Autosomal recessive
What sickle cell diseases affect the same gene? (2)
Beta-Thalassemia and sickle cell trait
what amino acids are replaced and substituted in SCD?
All have Val for Glu substitution but there can be variation in γ-globin expression
what happens due to decreased spleen function? how are these prevented?
Pneumococcal sepsis and meningitis. Penicillin given prophylactically and immunization
How do you treat SCD during crisis?
Narcotics, hydration to increase blood volume, and nasal inhalation of oxygen to combat hypoxia
Treatments to replace the sickle erythrocyte progenitors with normal erythrocyte progenitors?
Bone marrow or cord blood transplant for individuals with very severe cases
What is the result of blood transfusion?
suppress endogenous RBC production if at risk for stroke. Blood transfusion reduces the HbS concentration to below 30% and suppresses endogenous erythropoiesis.
Explain Hydroxyurea…please?!!
increases fetal hemoglobin levels possibly through changes in
microRNA expression, but is carcinogenic
what role does BCL11A have in hemoglobin?
and was found to inhibit gamma expression after birth
